For those wishing to test out kde4.3 or amarok 2.1beta or associated packages. I have written a HowTo in the wiki to help you with the kde-testing overlay. keep in mind about slotting and kdeprefix useflag though if you don't want to upgrade your 4.2 Here is the link for the wiki -- http://wiki.sabayonlinux.org/index.php? ... ng_overlay

If you check the wiki, use the search function and google you can find the answer to most of your questions.